%I #8 May 07 2012 12:53:11
%S 3,5,7,11,13,23,29,31,43,53,61,71,73,89,109,127,139,149,163,229,257,
%T 263,271,277,307,331,337,383,389,419,433,449,457,463,479,523,541,607,
%U 631,643,647,653,661,673,691,727,761,769,797,809,821,823,829,859,881
%N Primes p such that (5p^2-1)/4 is also prime.
%H Zak Seidov, <a href="/A182583/b182583.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n) = 2*A104012(n) + 1.
%t Select[Prime[Range[200]], PrimeQ[(5*#^2 - 1)/4] &] (* _T. D. Noe_, May 07 2012 *)
%Y Cf. A104012.
%K nonn
%O 1,1
%A _Zak Seidov_, May 06 2012
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